On the Natural Faculties

                                  By Galen

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                          On the Natural Faculties

                                  By Galen

                       Translated by Arthur John Brock


                                    Book Two

     1. In the previous book we demonstrated that not only
     Erasistratus, but also all others who would say anything to the
     purpose about urinary secretion, must acknowledge that the kidneys
     possess some faculty which attracts to them this particular
     quality existing in the urine. Besides this we drew attention to
     the fact that the urine is not carried through the kidneys into
     the bladder by one method, the blood into parts of the animal by
     another, and the yellow bile separated out on yet another
     principle. For when once there has been demonstrated in any one
     organ, the drawing, or so-called epispastic faculty, there is then
     no difficulty in transferring it to the rest. Certainly Nature did
     not give a power such as this to the kidneys without giving it
     also to the vessels which abstract the biliary fluid, nor did she
     give it to the latter without also it to each of the other parts.
     And, assuredly, if this is true, we must marvel that Erasistratus
     should make statements concerning the delivery of nutriment from
     the food-canal which are so false as to be detected even by
     Asclepiades. Now, Erasistratus considers it absolutely certain
     that, if anything flows from the veins, one of two things must
     happen: either a completely empty space will result, or the
     contiguous quantum of fluid will run in and take the place of that
     which has been evacuated. Asclepiades, however, holds that not one
     of two, but one of three things must be said to result in the
     emptied vessels: either there will be an entirely empty space, or
     the contiguous portion will flow in, or the vessel will contract.
     For whereas, in the case of reeds and tubes it is true to say
     that, if these be submerged in water, and are emptied of the air
     which they contain in their lumens, then either a completely empty
     space will be left, or the contiguous portion will move onwards;
     in the case of veins this no longer holds, since their coats can
     collapse and so fall in upon the interior cavity. It may be seen,
     then, how false this hypothesis- by Zeus, I cannot call it a
     demonstration!- of Erasistratus is.

     And, from another point of view, even if it were true, it is
     superfluous, if the stomach has the power of compressing the
     veins, as he himself supposed, and the veins again of contracting
     upon their contents and propelling them forwards. For, apart from
     other considerations, no plethora would ever take place in the
     body, if delivery of nutriment resulted merely from the tendency
     of a vacuum to become refilled. Now, if the compression of the
     stomach becomes weaker the further it goes, and cannot reach to an
     indefinite distance, and if, therefore, there is need of some
     other mechanism to explain why the blood is conveyed in all
     directions, then the principle of the refilling of a vacuum may be
     looked on as a necessary addition; there will not, however, be a
     plethora in any of the parts coming after the liver, or, if there
     be, it will be in the region of the heart and lungs; for the heart
     alone of the parts which come after the liver draws the nutriment
     into its right ventricle, thereafter sending it through the
     arterioid vein to the lungs (for Erasistratus himself will have it
     that, owing to the membranous excrescences, no other parts save
     the lungs receive nourishment from the heart). If, however, in
     order to explain how plethora comes about, we suppose the force of
     compression by the stomach to persist indefinitely, we have no
     further need of the principle of the refilling of a vacuum,
     especially if we assume contraction of the veins in addition- as
     is, again, agreeable to Erasistratus himself.

     2. Let me draw his attention, then, once again, even if he does
     not wish it, to the kidneys, and let me state that these confute
     in the very clearest manner such people as object to the principle
     of attraction. Nobody has ever said anything plausible, nor, as we
     previously showed, has anyone been able to discover, by any means,
     any other cause for the secretion of urine; we necessarily appear
     mad if we maintain that the urine passes into the kidneys in the
     form of vapour, and we certainly cut a poor figure when we talk
     about the tendency of a vacuum to become refilled; this idea is
     foolish in the case of blood, and impossible, nay, perfectly
     nonsensical, in the case of the urine.

     This, then, is one blunder made by those who dissociate themselves
     from the principle of attraction. Another is that which they make
     about the secretion of yellow bile. For in this case, too, it is
     not a fact that when the blood runs past the mouths [stomata] of
     the bile-ducts there will be a thorough separation out [secretion]
     of biliary waste-matter. "Well," say they, "let us suppose that it
     is not secreted but carried with the blood all over the body."
     But, you sapient folk, Erasistratus himself supposed that Nature
     took thought for the animals' future, and was workmanlike in her
     method; and at the same time he maintained that the biliary fluid
     was useless in every way for the animals. Now these two things are
     incompatible. For how could Nature be still looked on as
     exercising forethought for the animal when she allowed a noxious
     humour such as this to be carried off and distributed with the

     This, however, is a small matter. I shall again point out here the
     greatest and most obvious error. For if the yellow bile adjusts
     itself to the narrower vessels and stomata, and the blood to the
     wider ones, for no other reason than that blood is thicker and
     bile thinner, and that the stomata of the veins are wider and
     those of the bile-ducts narrower, then it is clear that this
     watery and serous superfluity, too, will run out into the
     bile-ducts quicker than does the bile, exactly in proportion as it
     is thinner than the bile! How is it, then, that it does not run
     out? "Because," it may be said, "urine is thicker than bile!" This
     was what one of our Erasistrateans ventured to say, herein clearly
     disregarding the evidence of his senses, although he had trusted
     these in the case of the bile and blood. For, if it be that we are
     to look on bile as thinner than blood because it runs more, then,
     since the serous residue passes through fine linen or lint or a or
     a sieve more easily even than does bile, by these tokens bile must
     also be thicker than the watery fluid. For here, again, there is
     no argument which will demonstrate that bile is thinner than the
     serous superfluities.

     But when a man shamelessly goes on using circumlocutions, and
     never acknowledges when he has had a fall, he is like the amateur
     wrestlers, who, when they have been overthrown by the experts and
     are lying on their backs on the ground, so far from recognizing
     their fall, actually seize their victorious adversaries by the
     necks and prevent them from getting away, thus supposing
     themselves to be the winners!

     3. Thus, every hypothesis of channels as an explanation of natural
     functioning is perfect nonsense. For, if there were not an inborn
     faculty given by Nature to each one of the organs at the very
     beginning, then animals could not continue to live even for a few
     days, far less for the number of years which they actually do. For
     let us suppose they were under no guardianship, lacking in
     creative ingenuity and forethought; let us suppose they were
     steered only by material forces, and not by any special faculties
     (the one attracting what is proper to it, another rejecting what
     is foreign, and yet another causing alteration and adhesion of the
     matter destined to nourish it); if we suppose this, I am sure it
     would be ridiculous for us to discuss natural, or, still more,
     psychical, activities- or, in fact, life as a whole.

     For there is not a single animal which could live or endure for
     the shortest time if, possessing within itself so many different
     parts, it did not employ faculties which were attractive of what
     is appropriate, eliminative of what is foreign, and alterative of
     what is destined for nutrition. On the other hand, if we have
     these faculties, we no longer need channels, little or big,
     resting on an unproven hypothesis, for explaining the secretion of
     urine and bile, and the conception of some favourable situation
     (in which point alone Erasistratus shows some common sense, since
     he does regard all the parts of the body as having been well and
     truly placed and shaped by Nature).

     But let us suppose he remained true to his own statement that
     Nature is "artistic"- this Nature which, at the beginning, well
     and truly shaped and disposed all the parts of the animal, and,
     after carrying out this function (for she left nothing undone),
     brought it forward to the light of day, endowed with certain
     faculties necessary for its very existence, and, thereafter,
     gradually increased it until it reached its due size. If he argued
     consistently on this principle, I fail to see how he can continue
     to refer natural functions to the smallness or largeness of
     canals, or to any other similarly absurd hypothesis. For this
     Nature which shapes and gradually adds to the parts is most
     certainly extended throughout their whole substance. Yes indeed,
     she shapes and nourishes and increases them through and through,
     not on the outside only. For Praxiteles and Phidias and all the
     other statuaries used merely to decorate their material on the
     outside, in so far as they were able to touch it; but its inner
     parts they left unembellished, unwrought, unaffected by art or
     forethought, since they were unable to penetrate therein and to
     reach and handle all portions of the material. It is not so,
     however, with Nature. Every part of a bone she makes bone, every
     part of the flesh she makes flesh, and so with fat and all the
     rest; there is no part which she has not touched, elaborated, and
     embellished. Phidias, on the other hand, could not turn wax into
     ivory and gold, nor yet gold into wax: for each of these remains
     as it was at the commencement, and becomes a perfect statue simply
     by being clothed externally in a form and artificial shape. But
     Nature does not preserve the original character of any kind of
     matter; if she did so, then all parts of the animal would be
     blood- that blood, namely, which flows to the semen from the
     impregnated female and which is, so to speak, like the statuary's
     wax, a single uniform matter, subjected to the artificer. From
     this blood there arises no part of the animal which is as red and
     moist [as blood is], for bone, artery, vein, nerve, cartilage,
     fat, gland, membrane, and marrow are not blood, though they arise
     from it.

     I would then ask Erasistratus himself to inform me what the
     altering, coagulating, and shaping agent is. He would doubtless
     say, "Either Nature or the semen," meaning the same thing in both
     cases, but explaining it by different devices. For that which was
     previously semen, when it begins to procreate and to shape the
     animal, becomes, so to say, a special nature. For in the same way
     that Phidias possessed the faculties of his art even before
     touching his material, and then activated these in connection with
     this material (for every faculty remains inoperative in the
     absence of its proper material), so it is with the semen: its
     faculties it possessed from the beginning, while its activities it
     does not receive from its material, but it manifests them in
     connection therewith.

     And, of course, if it were to be overwhelmed with a great quantity
     of blood, it would perish, while if it were to be entirely
     deprived of blood it would remain inoperative and would not turn
     into a nature. Therefore, in order that it may not perish, but may
     become a nature in place of semen, there must be an afflux to it
     of a little blood- or, rather, one should not say a little, but a
     quantity commensurate with that of the semen. What is it then that
     measures the quantity of this afflux? What prevents more from
     coming? What ensures against a deficiency? What is this third
     overseer of animal generation that we are to look for, which will
     furnish the semen with a due amount of blood? What would
     Erasistratus have said if he had been alive, and had been asked
     this question? Obviously, the semen itself. This, in fact, is the
     artificer analogous with Phidias, whilst the blood corresponds to
     the statuary's wax.

     Now, it is not for the wax to discover for itself how much of it
     is required; that is the business of Phidias. Accordingly the
     artificer will draw to itself as much blood as it needs. Here,
     however, we must pay attention and take care not unwittingly to
     credit the semen with reason and intelligence; if we were to do
     this, we would be making neither semen nor a nature, but an actual
     living animal. And if we retain these two principles- that of
     proportionate attraction and that of the non-participation of
     intelligence- we shall ascribe to the semen a faculty for
     attracting blood similar to that possessed by the lodestone for
     iron. Here, then, again, in the case of the semen, as in so many
     previous instances, we have been compelled to acknowledge some
     kind of attractive faculty.

     And what is the semen? Clearly the active principle of the animal,
     the material principle being the menstrual blood. Next, seeing
     that the active principle employs this faculty primarily,
     therefore, in order that any one of the things fashioned by it may
     come into existence, it [the principle] must necessarily be
     possessed of its own faculty. How, then, was Erasistratus unaware
     of it, if the primary function of the semen be to draw to itself a
     due proportion of blood? Now, this fluid would be in due
     proportion if it were so thin and vaporous, that, as soon as it
     was drawn like dew into every part of the semen, it would
     everywhere cease to display its own particular character; for so
     the semen will easily dominate and quickly assimilate it- in fact,
     will use it as food. It will then, I imagine, draw to itself a
     second and a third quantum, and thus by feeding it acquires for
     itself considerable bulk and quantity. In fact, the alterative
     faculty has now been discovered as well, although about this also
     has not written a word. And, thirdly the shaping faculty will
     become evident, by virtue of which the semen firstly surrounds
     itself with a thin membrane like a kind of superficial
     condensation; this is what was described by Hippocrates in the
     sixth-day birth, which, according to his statement, fell from the
     singing-girl and resembled the pellicle of an egg. And following
     this all the other stages will occur, such as are described by him
     in his work "On the Child's Nature."

     But if each of the parts formed were to remain as small as when it
     first came into existence, of what use would that be? They have,
     then, to grow. Now, how will they grow? By becoming extended in
     all directions and at the same time receiving nourishment. And if
     you will recall what I previously said about the bladder which the
     children blew up and rubbed, you will also understand my meaning
     better as expressed in what I am now about to say.

     Imagine the heart to be, at the beginning, so small as to differ
     in no respect from a millet-seed, or, if you will, a bean; and
     consider how otherwise it is to become large than by being
     extended in all directions and acquiring nourishment throughout
     its whole substance, in the way that, as I showed a short while
     ago, the semen is nourished. But even this was unknown to
     Erasistratus- the man who sings the artistic skill of Nature! He
     imagines that animals grow like webs, ropes, sacks, or baskets,
     each of which has, woven on to its end or margin, other material
     similar to that of which it was originally composed.

     But this, most sapient sir, is not growth, but genesis! For a bag,
     sack, garment, house, ship, or the like is said to be still coming
     into existence [undergoing genesis] so long as the appropriate
     form for the sake of which it is being constructed by the
     artificer is still incomplete. Then, when does it grow? Only when
     the basket, being complete, with a bottom, a mouth, and a belly,
     as it were, as well as the intermediate parts, now becomes larger
     in all these respects. "And how can this happen?" someone will
     ask. Only by our basket suddenly becoming an animal or a plant;
     for growth belongs to living things alone. Possibly you imagine
     that a house grows when it is being built, or a basket when being
     plated, or a garment when being woven? It is not so, however.
     Growth belongs to that which has already been completed in respect
     to its form, whereas the process by which that which is still
     becoming attains its form is termed not growth but genesis. That
     which is, grows, while that which is not, becomes.

     4. This also was unknown to Erasistratus, whom nothing escaped, if
     his followers speak in any way truly in maintaining that he was
     familiar with the Peripatetic philosophers. Now, in so far as he
     acclaims Nature as being an artist in construction, even I
     recognize the Peripatetic teachings, but in other respects he does
     not come near them. For if anyone will make himself acquainted
     with the writings of Aristotle and Theophrastus, these will appear
     to him to consist of commentaries on the Nature-lore [physiology]
     of Hippocrates- according to which the principles of heat, cold,
     dryness and moisture act upon and are acted upon by one another,
     the hot principle being the most active, and the cold coming next
     to it in power; all this was stated in the first place by
     Hippocrates and secondly by Aristotle. Further, it is at once the
     Hippocratic and the Aristotelian teaching that the parts which
     receive that nourishment throughout their whole substance, and
     that, similarly, processes of mingling and alteration involve the
     entire substance. Moreover, that digestion is a species of
     alteration- a transmutation of the nutriment into the proper
     quality of the thing receiving it; that blood-production also is
     an alteration, and nutrition as well; that growth results from
     extension in all directions, combined with nutrition; that
     alteration is effected mainly by the warm principle, and that
     therefore digestion, nutrition, and the generation of the various
     humours, as well as the qualities of the surplus substances,
     result from the innate heat; all these and many other points
     besides in regard to the aforesaid faculties, the origin of
     diseases, and the discovery of remedies, were correctly stated
     first by Hippocrates of all writers whom we know, and were in the
     second place correctly expounded by Aristotle. Now, if all these
     views meet with the approval of the Peripatetics, as they
     undoubtedly do, and if none of them satisfy Erasistratus, what can
     the Erasistrateans possibly mean by claiming that their leader was
     associated with these philosophers? The fact is, they revere him
     as a god, and think that everything he says is true. If this be
     so, then we must suppose the Peripatetics to have strayed very far
     from truth, since they approve of none of the ideas of
     Erasistratus. And, indeed, the disciples of the latter produce his
     connection with the Peripatetics in order to furnish his
     Nature-lore with a respectable pedigree.

     Now, let us reverse our argument and put it in a different way
     from that which we have just employed. For if the Peripatetics
     were correct in their teaching about Nature, there could be
     nothing more absurd than the contentions of Erasistratus. And, I
     will leave it to the Erasistrateans themselves to decide; they
     must either advance the one proposition or the other. According to
     the former one the Peripatetics had no accurate acquaintance with
     Nature, and according to the second, Erasistratus. It is my task,
     then, to point out the opposition between the two doctrines, and
     theirs to make the choice....

     But they certainly will not abandon their reverence for
     Erasistratus. Very well, then; let them stop talking about the
     Peripatetic philosophers. For among the numerous physiological
     teachings regarding the genesis and destruction of animals, their
     health, their diseases, and the methods of treating these, there
     will be found one only which is common to Erasistratus and the
     Peripatetics- namely, the view that Nature does everything for
     some purpose, and nothing in vain.

     But even as regards this doctrine their agreement is only verbal;
     in practice Erasistratus makes havoc of it a thousand times over.
     For, according to him, the spleen was made for no purpose, as also
     the omentum; similarly, too, the arteries which are inserted into
     kidneys- although these are practically the largest of all those
     that spring from the great artery [aorta]! And to judge by the
     Erasistratean argument, there must be countless other useless
     structures; for, if he knows nothing at all about these
     structures, he has little more anatomical knowledge than a
     butcher, while, if he is acquainted with them and yet does not
     state their use, he clearly imagines that they were made for no
     purpose, like the spleen. Why, however, should I discuss these
     structures fully, belonging as they do to the treatise "On the Use
     of Parts," which I am personally about to complete?

     Let us, then, sum up again this same argument, and, having said a
     few words more in answer to the Erasistrateans, proceed to our
     next topic. The fact is, these people seem to me to have read none
     of Aristotle's writings, but to have heard from others how great
     an authority he was on "Nature," and that those of the Porch
     follow in the steps of his Nature-lore; apparently they then
     discovered a single one of the current ideas which is common to
     Aristotle and Erasistratus, and made up some story of a connection
     between Erasistratus and these people. That Erasistratus, however,
     has no share in the Nature-lore of Aristotle is shown by an
     enumeration of the aforesaid doctrines, which emanated first from
     Hippocrates, secondly from Aristotle, thirdly from the Stoics
     (with a single modification, namely, that for them the qualities
     are bodies). Perhaps, however, they will maintain that it was in
     the matter of logic that Erasistratus associated himself with the
     Peripatetic philosophers? Here they show ignorance of the fact
     that these philosophers never brought forward false or
     inconclusive arguments, while the Erasistratean books are full of

     So perhaps somebody may already be asking, in some surprise, what
     possessed Erasistratus that he turned so completely from the
     doctrines of Hippocrates, and why it is that he takes away the
     attractive faculty from the biliary passages in the liver- for we
     have sufficiently discussed the kidneys- alleging [as the cause of
     bile-secretion] a favourable situation, the narrowness of vessels,
     and a common space into which the veins from the gateway [of the
     liver] conduct the unpurified blood, and from which, in the first
     place, the [biliary] passages take over the bile, and secondly,
     the [branches] of the vena cava take over the purified blood. For
     it would not only have done him no harm to have mentioned the idea
     of attraction, but he would thereby have been able to get rid of
     countless other disputed questions.

     5. At the actual moment, however, the Erasistrateans are engaged
     in a considerable battle, not only with others but also amongst
     themselves, and so they cannot explain the passage from the first
     book of the "General Principles," in which Erasistratus says,
     "Since there are two kinds of vessels opening at the same place,
     the one kind extending to the gall-bladder and the other to the
     vena cava, the result is that, of the nutriment carried up from
     the alimentary canal, that part which fits both kinds of stomata
     is received into both kinds of vessels, some being carried into
     the gall-bladder, and the rest passing over into the vena cava."
     For it is difficult to say what we are to understand by the words
     "opening at the same place" which are written at the beginning of
     this passage. Either they mean there is a junction between the
     termination of the vein which is on the concave surface of the
     liver and two other vascular terminations (that of the vessel on
     the convex surface of the liver and that of the bile-duct), or, if
     not, then we must suppose that there is, as it were, a common
     space for all three vessels, which becomes filled from the lower
     vein, and empties itself both into the bile-duct and into the
     branches of the vena cava. Now, there are many difficulties in
     both of these explanations, but if I were to state them all, I
     should find myself inadvertently writing an exposition of the
     teaching of Erasistratus, instead of carrying out my original
     undertaking. There is, however, one difficulty common to both
     these explanations, namely, that the whole of the blood does not
     become purified. For it ought to fall into the bile-duct as into a
     kind of sieve, instead of going (running, in fact, rapidly) past
     it, into the larger stoma, by virtue of the impulse of anadosis.

     Are these, then, the only inevitable difficulties in which the
     argument of Erasistratus becomes involved through his
     disinclination to make any use of the attractive faculty, or is it
     that the difficulty is greatest here, and also so obvious that
     even a child could not avoid seeing it?

     6. And if one looks carefully into the matter one will find that
     even Erasistratus' reasoning on the subject of nutrition, which he
     takes up in the second book of his "General Principles," fails to
     escape this same difficulty. For, having conceded one premise to
     the principle that matter tends to fill a vacuum, as we previously
     showed, he was only able to draw a conclusion in the case of the
     veins and their contained blood. That is to say, when blood is
     running away through the stomata of the veins, and is being
     dispersed, then, since an absolutely empty space cannot result,
     and the veins cannot collapse (for this was what he overlooked),
     it was therefore shown to be necessary that the that the adjoining
     quantum of fluid should flow in and fill the place of the fluid
     evacuated. It is in this way that we may suppose the veins to be
     nourished; they get the benefit of the blood which they contain.
     But how about the nerves? For they do not also contain blood. One
     might obviously say that they draw their supply from the veins.
     But Erasistratus will not have it so. What further contrivance,
     then, does he suppose? He says that a nerve has within itself
     veins and arteries, like a rope woven by Nature out of three
     different strands. By means of this hypothesis he imagined that
     his theory would escape from the idea of attraction. For if the
     nerve contain within itself a blood-vessel it will no longer need
     the adventitious flow of other blood from the real vein lying
     adjacent; this fictitious vessel, perceptible only in theory, will
     suffice it for nourishment.

     But this, again, is succeeded by another similar difficulty. For
     this small vessel will nourish itself, but it will not be able to
     nourish this adjacent simple nerve or artery, unless these possess
     some innate proclivity for attracting nutriment. For how could the
     nerve, being simple, attract its nourishment, as do the composite
     veins, by virtue of the tendency of a vacuum to become refilled?
     For, although according to Erasistratus, it contains within itself
     a cavity of sorts, this is not occupied with blood, but with
     psychic pneuma, and we are required to imagine the nutriment
     introduced, not into this cavity, but into the vessel containing
     it, whether it needs merely to be nourished, or to grow as well.
     How, then, are we to imagine it introduced? For this simple vessel
     [i.e. nerve] is so small- as are also the other two- that if you
     prick it at any part with the finest needle you will tear the
     whole three of them at once. Thus there could never be in it a
     perceptible space entirely empty. And an emptied space which
     merely existed in theory could not compel the adjacent fluid to
     come and fill it.

     At this point, again, I should like Erasistratus himself to answer
     regarding this small elementary nerve, whether it is actually one
     and definitely continuous, or whether it consists of many small
     bodies, such as those assumed by Epicurus, Leucippus, and
     Democritus. For I see that the Erasistrateans are at variance on
     this subject. Some of them consider it one and continuous, for
     otherwise, as they say, he would not have called it simple; and
     some venture to resolve it into yet other elementary bodies. But
     if it be one and continuous, then what is evacuated from it in the
     so-called insensible transpiration of the physicians will leave no
     empty space in it; otherwise it would not be one body but many,
     separated by empty spaces. But if it consists of many bodies, then
     we have "escaped by the back door," as the saying is, to
     Asclepiades, seeing that we have postulated certain inharmonious
     elements. Once again, then, we must call Nature "inartistic"; for
     this necessarily follows the assumption of such elements.

     For this reason some of the Erasistrateans seem to me to have done
     very foolishly in reducing the simple vessels to elements such as
     these. Yet it makes no difference to me, since the theory of both
     parties regarding nutrition will be shown to be absurd. For in
     these minute simple vessels constituting the large perceptible
     nerves, it is impossible, according to the theory of those who
     would keep the former continuous, that any "refilling of a vacuum"
     should take place, since no vacuum can occur in a continuum even
     if anything does run away; for the parts left come together (as is
     seen in the case of water) and again become one, taking up the
     whole space of that which previously separated them. Nor will any
     "refilling" occur if we accept the argument of the other
     Erasistrateans, since none of their elements need it. For this
     principle only holds of things which are perceptible, and not of
     those which exist merely in theory; this Erasistratus expressly
     acknowledges, for he states that it is not a vacuum such as this,
     interspersed in small portions among the corpuscles, that his
     various treatises deal with, but a vacuum which is clear,
     perceptible, complete in itself, large in size, evident, or
     however else one cares to term it (for, what Erasistratus himself
     says is, that "there cannot be a perceptible space which is
     entirely empty"; while I, for my part, being abundantly equipped
     with terms which are equally elucidatory, at least in relation to
     the present topic of discussion, have added them as well).

     Thus it seems to me better that we also should help the
     Erasistrateans with some contribution, since we are on the
     subject, and should advise those who reduce the vessel called
     primary and simple by Erasistratus into other elementary bodies to
     give up their opinion; for not only do they gain nothing by it,
     but they are also at variance with Erasistratus in this matter.
     That they gain nothing by it has been clearly demonstrated; for
     this hypothesis could not escape the difficulty regarding
     nutrition. And it also seems perfectly evident to me that this
     hypothesis is not in consonance with the view of Erasistratus,
     when it declares that what he calls simple and primary is
     composite, and when it destroys the principle of Nature's artistic
     skill. For, if we do not grant a certain unity of substance to
     these simple structures as well, and if we arrive eventually at
     inharmonious and indivisible elements, we shall most assuredly
     deprive Nature of her artistic skill, as do all the physicians and
     philosophers who start from this hypothesis. For, according to
     such a hypothesis, Nature does not precede, but is secondary to
     the parts of the animal. Now, it is not the province of what comes
     secondarily, but of what pre-exists, to shape and to construct.
     Thus we must necessarily suppose that the faculties of Nature, by
     which she shapes the animal, and makes it grow and receive
     nourishment, are present from the seed onwards; whereas none of
     these inharmonious and non-partite corpuscles contains within
     itself any formative, incremental, nutritive, or, in a word, any
     artistic power; it is, by hypothesis, unimpressionable and
     untransformable, whereas, as we have previously shown, none of the
     processes mentioned takes place without transformation,
     alteration, and complete intermixture. And, owing to this
     necessity, those who belong to these sects are unable to follow
     out the consequences of their supposed elements, and they are all
     therefore forced to declare Nature devoid of art. It is not from
     us, however, that the Erasistrateans should have learnt this, but
     from those very philosophers who lay most stress on a preliminary
     investigation into the elements of all existing things.

     Now, one can hardly be right in supposing that Erasistratus could
     reach such a pitch of foolishness as to be recognizing the logical
     consequences of this theory, and that, while assuming Nature to be
     artistically creative, he would at the same time break up
     substance into insensible, inharmonious, and untransformable
     elements. If, however, he will grant that there occurs in the
     elements a process of alteration and transformation, and that
     there exists in them unity and continuity, then that simple vessel
     of his (as he himself names it) will turn out to be single and
     uncompounded. And the simple vein will receive nourishment from
     itself, and the nerve and artery from the vein. How, and in what
     way? For, when we were at this point before, we drew attention to
     the disagreement among the Erasistrateans, and we showed that the
     nutrition of these simple vessels was impraticable according to
     the teachings of both parties, although we did not hesitate to
     adjudicate in their quarrel and to do Erasistratus the honour of
     placing him in the better sect.

     Let our argument, then, be transferred again to the doctrine which
     assumes this elementary nerve to be a single, simple, and entirely
     unified structure, and let us consider how it is to be nourished;
     for what is discovered here will at once be found to be common
     also to the school of Hippocrates.

     It seems to me that our enquiry can be most rigorously pursued in
     subjects who are suffering from illness and have become very
     emaciated, since in these people all parts of the body are
     obviously atrophied and thin, and in need of additional substance
     and feeding-up; for the same reason the ordinary perceptible
     nerve, regarding which we originally began this discussion, has
     become thin, and requires nourishment. Now, this contains within
     itself various parts, namely, a great many of these primary,
     invisible, minute nerves, a few simple arteries, and similarly
     also veins. Thus, all its elementary nerves have themselves also
     obviously become emaciated; for, if they had not, neither would
     the nerve as a whole; and of course, in such a case, the whole
     nerve cannot require nourishment without each of these requiring
     it too. Now, if on the one hand they stand in need of feeding-up,
     and if on the other the principle of the refilling of a vacuum can
     give them no help- both by reason of the difficulties previously
     mentioned and the actual thinness, as I shall show- we must then
     seek another cause for nutrition.

     How is it, then, that the tendency of a vacuum to become refilled
     is unable to afford nourishment to one in such a condition?
     Because its rule is that only so much of the contiguous matter
     should succeed as has flowed away. Now this is sufficient for
     nourishment in the case of those who are in good condition, for,
     in them, what is presented must be equal to what has flowed away.
     But in the case of those who are very emaciated and who need a
     great restoration of nutrition, unless what was presented were
     many times greater than what has been emptied out, they would
     never be able to regain their original habit. It is clear,
     therefore, that these parts will have to exert a greater amount of
     attraction, in so far as their requirements are greater. And I
     fail to understand how Erasistratus does not perceive that here
     again he is putting the cart before the horse. Because, in the
     case of the sick, there must be a large amount of presentation in
     order to feed them up, he argues that the factor of "refilling"
     must play an equally large part. And how could much presentation
     take place if it were not preceded by an abundant delivery of
     nutriment? And if he calls the conveyance of food through the
     veins delivery, and its assumption by each of these simple and
     visible nerves and arteries not delivery but distribution, as some
     people have thought fit to name it, and then ascribes conveyance
     through the veins to the principle of vacuum refilling alone, let
     him explain to us the assumption of food by the hypothetical
     elements. For it has been shown that at least in relation to these
     there is no question of the refilling of a vacuum being in
     operation, and especially where the parts are very attenuated. It
     is worth while listening to what Erasistratus says about these
     cases in the second book of his "General Principles": "In the
     ultimate simple [vessels], which are thin and narrow, presentation
     takes place from the adjacent vessels, the nutriment being
     attracted through the sides of the vessels and deposited in the
     empty spaces left by the matter which has been carried away." Now,
     in this statement firstly I admit and accept the words "through
     the sides." For, if the simple nerve were actually to take in the
     food through its mouth, it could not distribute it through its
     whole substance; for the mouth is dedicated to the psychic pneuma.
     It can, however, take it in through its sides from the adjacent
     simple vein. Secondly, I also accept in Erasistratus' statement
     the expression which precedes "through the sides." What does this
     say? "The nutriment being attracted through the sides of the
     vessels." Now I, too, agree that it is attracted, but it has been
     previously shown that this is not through the tendency of
     evacuated matter to be replaced.

     7. Let us, then, consider together how it is attracted. How else
     than in the way that iron is attracted by the lodestone, the
     latter having a faculty attractive of this particular quality
     [existing in iron]? But if the beginning of anadosis depends on
     the squeezing action of the stomach, and the whole movement
     thereafter on the peristalsis and propulsive action of the veins,
     as well as on the traction exerted by each of the parts which are
     undergoing nourishment, then we can abandon the principle of
     replacement of evacuated matter, as not being suitable for a man
     who assumes Nature to be a skilled artist; thus we shall also have
     avoided the contradiction of Asclepiades though we cannot refute
     it: for the disjunctive argument used for the purposes of
     demonstration is, in reality, disjunctive not of two but of three
     alternatives; now, if we treat the disjunction as a disjunction of
     two alternatives, one of the two propositions assumed in
     constructing our proof must be false; and if as a disjunctive of
     three alternatives, no conclusion will be arrived at.

     8. Now Erasistratus ought not to have been ignorant of this if he
     had ever had anything to do with the Peripatetics- even in a
     dream. Nor, similarly, should he have been unacquainted with the
     genesis of the humours, about which, not having even anything
     moderately plausible to say, he thinks to deceive us by the excuse
     that the consideration of such matters is not the least useful.
     Then, in Heaven's name, is it useful to know how food is digested
     in the stomach, but unnecessary to know how bile comes into
     existence in the veins? Are we to pay attention merely to the
     evacuation of this humour, and not to its genesis? As though it
     were not far better to prevent its excessive development from the
     beginning than to give ourselves all the trouble of expelling it!
     And it is a strange thing to be entirely unaware as to whether its
     genesis is to be looked on as taking place in the body, or whether
     it comes from without and is contained in the food. For, if it was
     right to raise this problem, why should we not make investigations
     concerning the blood as well- whether it takes its origin in the
     body, or is distributed through the food as is maintained by those
     who postulate homoeomeries? Assuredly it would be much more useful
     to investigate what kinds of food are suited, and what kinds
     unsuited, to the process of blood-production rather than to
     enquire into what articles of diet are easily mastered by the
     activity of the stomach, and what resist and contend with it. For
     the choice of the latter bears reference merely to digestion,
     while that of the former is of importance in regard to the
     generation of useful blood. For it is not equally important
     whether the aliment be imperfectly chylified in the stomach or
     whether it fail to be turned into useful blood. Why is
     Erasistratus not ashamed to distinguish all the various kinds of
     digestive failure and all the occasions which give rise to them,
     whilst in reference to the errors of blood-production he does not
     utter a single word- nay, not a syllable? Now, there is certainly
     to be found in the veins both thick and thin blood; in some people
     it is redder, in others yellower, in some blacker, in others more
     of the nature of phlegm. And one who realizes that it may smell
     offensively not in one way only, but in a great many different
     respects (which cannot be put into words, although perfectly
     appreciable to the senses), would, I imagine, condemn in no
     measured terms the carelessness of Erasistratus in omitting a
     consideration so essential to the practice of our art.

     Thus it is clear what errors in regard to the subject of dropsies
     logically follow this carelessness. For, does it not show the most
     extreme carelessness to suppose that the blood is prevented from
     going forward into the liver owing to the narrowness of the
     passages, and that dropsy can never occur in any other way? For,
     to imagine that dropsy is never caused by the spleen or any other
     part, but always by induration of the liver, is the standpoint of
     a man whose intelligence is perfectly torpid and who is quite out
     of touch with things that happen every day. For, not merely once
     or twice, but frequently, we have observed dropsy produced by
     chronic haemorrhoids which have been suppressed, or which, through
     immoderate bleeding, have given the patient a severe chill;
     similarly, in women, the complete disappearance of the monthly
     discharge, or an undue evacuation such as is caused by violent
     bleeding from the womb, often provoke dropsy; and in some of them
     the so-called female flux ends in this disorder. I leave out of
     account the dropsy which begins in the flanks or in any other
     susceptible part; this clearly confutes Erasistratus' assumption,
     although not so obviously as does that kind of dropsy which is
     brought about by an excessive chilling of the whole constitution;
     this, which is the primary reason for the occurrence of dropsy,
     results from a failure of blood-production, very much like the
     diarrhoea which follows imperfect digestion of food; certainly in
     this kind of dropsy neither the liver nor any other viscus becomes

     The learned Erasistratus, however, overlooks- nay, despises- what
     neither Hippocrates, Diocles, Praxagoras, nor indeed any of the
     best philosophers, whether Plato, Aristotle, or Theophrastus; he
     passes by whole functions as though it were but a trifling and
     casual department of medicine which he was neglecting, without
     deigning to argue whether or not these authorities are right in
     saying that the bodily parts of all animals are governed by the
     Warm, the Cold, the Dry and the Moist, the one pair being active
     the other passive, and that among these the Warm has most power in
     connection with all functions, but especially with the genesis of
     the humours. Now, one cannot be blamed for not agreeing with all
     these great men, nor for imagining that one knows more than they;
     but not to consider such distinguished teaching worthy either of
     contradiction or even mention shows an extraordinary arrogance.

     Now, Erasistratus is thoroughly small-minded and petty to the last
     degree in all his disputations- when, for instance, in his
     treatise "On Digestion," he argues jealously with those who
     consider that this is a process of putrefaction of the food; and,
     in his work "On Anadosis," with those who think that the anadosis
     of blood through the veins results from the contiguity of the
     arteries; also, in his work "On Respiration," with those who
     maintain that the air is forced along by contraction. Nay, he did
     not even hesitate to contradict those who maintain that the urine
     passes into the bladder in a vaporous state, as also those who say
     that imbibed fluids are carried into the lung. Thus he delights to
     choose always the most valueless doctrines, and to spend his time
     more and more in contradicting these; whereas on the subject of
     the origin of blood (which is in no way less important than the
     chylification of food in the stomach) he did not deign to dispute
     with any of the ancients, nor did he himself venture to bring
     forward any other opinion, despite the fact that at the beginning
     of his treatise on "General Principles" he undertook to say how
     all the various natural functions take place, and through what
     parts of the animal! Now, is it possible that, when the faculty
     which naturally digests food is weak, the animal's digestion
     fails, whereas the faculty which turns the digested food into
     blood cannot suffer any kind of impairment? Are we to suppose this
     latter faculty alone to be as tough as steel and unaffected by
     circumstances? Or is it that weakness of this faculty will result
     in something else than dropsy? The fact, therefore, that
     Erasistratus, in regard to other matters, did not hesitate to
     attack even the most trivial views, whilst in this he neither
     dared to contradict his predecessors nor to advance any new view
     of his own, proves plainly that he recognized the fallacy of his
     own way of thinking.

     For what could a man possibly say about blood who had no use for
     innate heat? What could he say about yellow or black bile, or
     phlegm? Well, of course, he might say that the bile could come
     directly from without, mingled with the food! Thus Erasistratus
     practically says so in the following words: "It is of no value in
     practical medicine to find out whether fluid of this kind arises
     from the elaboration of food in the stomach-region, or whether it
     reaches the body because it is mixed with the food taken in from
     outside." But my very good Sir, you most certainly maintain also
     that this humour has to be evacuated from the animal, and that it
     causes great pain if it be not evacuated. How, then, if you
     suppose that no good comes from the bile, do you venture to say
     that an investigation into its origin is of no value in medicine?

     Well, let us suppose that it is contained in the food, and not
     specifically secreted in the liver (for you hold these two things
     possible). In this case, it will certainly make a considerable
     difference whether the ingested food contains a minimum or a
     maximum of bile; for the one kind is harmless, whereas that
     containing a large quantity of bile, owing to the fact that it
     cannot be properly purified in the liver, will result in the
     various affections- particularly jaundice- which Erasistratus
     himself states to occur where there is much bile. Surely, then, it
     is most essential for the physician to know in the first place,
     that the bile is contained in the food itself from outside, and,
     secondly, that for example, beet contains a great deal of bile,
     and bread very little, while olive oil contains most, and wine
     least of all, and all the other articles of diet different
     quantities. Would it not be absurd for any one to choose
     voluntarily those articles which contain more bile, rather than
     those containing less?

     What, however, if the bile is not contained in the food, but comes
     into existence in the animal's body? Will it not also be useful to
     know what state of the body is followed by a greater, and what by
     a smaller occurrence of bile? For obviously it is in our power to
     alter and transmute morbid states of the body- in fact, to give
     them a turn for the better. But if we did not know in what respect
     they were morbid or in what way they diverged from the normal, how
     should we be able to ameliorate them?

     Therefore it is not useless in treatment, as Erasistratus says, to
     know the actual truth about the genesis of bile. Certainly it is
     not impossible, or even difficult to discover that the reason why
     honey produces yellow bile is not that it contains a large
     quantity of this within itself, but because it [the honey]
     undergoes change, becoming altered and transmuted into bile. For
     it would be bitter to the taste if it contained bile from the
     outset, and it would produce an equal quantity of bile in every
     person who took it. The facts, however, are not so. For in those
     who are in the prime of life, especially if they are warm by
     nature and are leading a life of toil, the honey changes entirely
     into yellow bile. Old people, however, it suits well enough,
     inasmuch as the alteration which it undergoes is not into bile,
     but into blood. Erasistratus, however, in addition to knowing
     nothing about this, shows no intelligence even in the division of
     his argument; he says that it is of no practical importance to
     investigate whether the bile is contained in the food from the
     beginning or comes into existence as a result of gastric
     digestion. He ought surely to have added something about its
     genesis in liver and veins, seeing that the old physicians and
     philosophers declare that it along with the blood is generated in
     these organs. But it is inevitable that people who, from the very
     outset, go astray, and wander from the right road, should talk
     such nonsense, and should, over and above this, neglect to search
     for the factors of most practical importance in medicine.

     Having come to this poi in the argument, I should like to ask
     those who declare that Erasistratus was very familiar with the
     Peripatetics, whether they know what Aristotle stated and
     demonstrated with regard to our bodies being compounded out of the
     Warm, the Cold, the Dry and the Moist, and how he says that among
     these the Warm is the most active, and that those animals which
     are by nature warmest have abundance of blood, whilst those that
     are colder are entirely lacking in blood, and consequently in
     winter lie idle and motionless, lurking in holes like corpses.
     Further, the question of the colour of the blood has been dealt
     with not only by Aristotle but also by Plato. Now I, for my part,
     as I have already said, did not set before myself the task of
     stating what has been so well demonstrated by the Ancients, since
     I cannot surpass these men either in my views or in my method of
     giving them expression. Doctrines, however, which they either
     stated without demonstration, as being self-evident (since they
     never suspected that there could be sophists so degraded as to
     contemn the truth in these matters), or else which they actually
     omitted to mention at all- these I propose to discover and prove.

     Now in reference to the genesis of the humours, I do not know that
     any one could add anything wiser than what has been said by
     Hippocrates, Aristotle, Praxagoras, Philotimus and many other
     among the Ancients. These men demonstrated that when the nutriment
     becomes altered in the veins by the innate heat, blood is produced
     when it is in moderation, and the other humours when it is not in
     proper proportion. And all the observed facts agree with this
     argument. Thus, those articles of food, which are by nature warmer
     are more productive of bile, while those which are colder produce
     more phlegm. Similarly of the periods of life, those which are
     naturally warmer tend more to bile, and the colder more to phlegm.
     Of occupations also, localities and seasons, and, above all, of
     natures themselves, the colder are more phlegmatic, and the warmer
     more bilious. Also cold diseases result from and warmer ones from
     yellow bile. There is not a single thing to be found which does
     not bear witness to the truth of this account. How could it be
     otherwise? For, seeing that every part functions in its own
     special way because of the manner in which the four qualities are
     compounded, it is absolutely necessary that the function
     [activity] should be either completely destroyed, or, at least
     hampered, by any damage to the qualities, and that thus the animal
     should fall ill, either as a whole, or in certain of its parts.

     Also the diseases which are primary and most generic are four in
     number, and differ from each other in warmth, cold, dryness and
     moisture. Now, Erasistratus himself confesses this, albeit
     unintentionally; for when he says that the digestion of food
     becomes worse in fever, not because the innate heat has ceased to
     be in due proportion, as people previously supposed, but because
     the stomach, with its activity impaired, cannot contract and
     triturate as before- then, I say, one may justly ask him what it
     is that has impaired the activity of the stomach.

     Thus, for example, when a bubo develops following an accidental
     wound gastric digestion does not become impaired until the patient
     has become fevered; neither the bubo nor the sore of itself
     impedes in any way or damages the activity of the stomach. But if
     fever occurs, the digestion at once deteriorates, and we are also
     right in saying that the activity of the stomach at once becomes
     impaired. We must add, however, by what it has been impaired. For
     the wound was not capable of impairing it, nor yet the bubo, for,
     if they had been, then they would have caused this damage before
     the fever as well. If it was not these that caused it, then it was
     the excess of heat (for these two symptoms occurred besides the
     bubo- an alteration in the arterial and cardiac movements and an
     excessive development of natural heat). Now the alteration of
     these movements will not merely not impair the function of the
     stomach in any way: it will actually prove an additional help
     among those animals in which, according to Erasistratus, the
     pneuma, which is propelled through the arteries and into the
     alimentary canal, is of great service in digestion; there is only
     left, then, the disproportionate heat to account for the damage to
     the gastric activity. For the pneuma is driven in more vigorously
     and continuously, and in greater quantity now than before; thus in
     this case, the animal whose digestion is promoted by pneuma will
     digest more, whereas the remaining factor- abnormal heat- will
     give them indigestion. For to say, on the one hand, that the
     pneuma has a certain property by virtue of which it promotes
     digestion, and then to say that this property disappears in cases
     of fever, is simply to admit the absurdity. For when they are
     again asked what it is that has altered the pneuma, they will only
     be able to reply, "the abnormal heat," and particularly if it be
     the pneuma in the food canal which is in question (since this does
     not come in any way near the bubo).

     Yet why do I mention those animals in which the property of the
     pneuma plays an important part, when it is possible to base one's
     argument upon human beings, in whom it is either of no importance
     at all, or acts quite faintly and feebly? But Erasistratus himself
     agrees that human beings digest badly in fevers, adding as the
     cause that the activity of the stomach has been impaired. He
     cannot, however, advance any other cause of this impairment than
     abnormal heat. But if it is not by accident that the abnormal heat
     impairs this activity, but by virtue of its own essence and power,
     then this abnormal heat must belong to the primary diseases. But,
     indeed, if disproportion of heat belongs to the primary diseases,
     it cannot but be that a proportionate blending [eucrasia] of the
     qualities produces the normal activity. For a disproportionate
     blend [dyscrasia] can only become a cause of the primary diseases
     through derangement of the eucrasia. That is to say, it is because
     the [normal] activities arise from the eucrasia that the primary
     impairments of these activities necessarily arise the from

     I think, then, it has been proved to the satisfaction of those who
     are capable of seeing logical consequences, that, even according
     to Erasistratus' own argument, the cause of the normal functions
     is eucrasia of the Warm. Now, this being so, there is nothing
     further to prevent us from saying that, in the case of each
     function, eucrasia is followed by the more, and dyscrasia by the
     less favourable alternative. And, therefore, if this be the case,
     we must suppose blood to be the outcome of proportionate, and
     yellow bile of disproportionate heat. So we naturally find yellow
     bile appearing in greatest quantity in ourselves at the warm
     periods of life, in warm countries, at warm seasons of the year,
     and when we are in a warm condition; similarly in people of warm
     temperaments, and in connection with warm occupations, modes of
     life, or diseases.

     And to be in doubt as to whether this humour has the genesis in
     the human body or is contained in the food is what you would
     expect from one who has- I will not say failed to see that, when
     those who are perfectly healthy have, under the compulsion of
     circumstances, to fast contrary to custom, their mouths become
     bitter and their urine bile-coloured, while they suffer from
     gnawing pains in the stomach- but has, as it were, just made a
     sudden entrance into the world, and is not yet familiar with the
     phenomena which occur there. Who, in fact, does not know that
     anything which is overcooked grows at first salt and afterwards
     bitter? And if you will boil honey itself, far the sweetest of all
     things, you can demonstrate that even this becomes quite bitter.
     For what may occur as a result of boiling in the case of other
     articles which are not warm by nature, exists naturally in honey;
     for this reason it does not become sweeter on being boiled, since
     exactly the same quantity of heat as is needed for the production
     of sweetness exists from beforehand in the honey. Therefore the
     external heat, which would be useful for insufficiently warm
     substances, becomes in the honey a source of damage, in fact an
     excess; and it is for this reason that honey, when boiled, can be
     demonstrated to become bitter sooner than the others. For the same
     reason it is easily transmuted into bile in those people who are
     naturally warm, or in their prime, since warm when associated with
     warm becomes readily changed into a disproportionate combination
     and turns into bile sooner than into blood. Thus we need a cold
     temperament and a cold period of life if we would have honey
     brought to the nature of blood. Therefore Hippocrates not
     improperly advised those who were naturally bilious not to take
     honey, since they were obviously of too warm a temperament. So
     also, not only Hippocrates, but all physicians say that honey is
     bad in bilious diseases but good in old age; some of them having
     discovered this through the indications afforded by its nature,
     and others simply through experiment, for the Empiricist
     physicians too have made precisely the same observation, namely,
     that honey is good for an old man and not for a young one, that it
     is harmful for those who are naturally bilious, and serviceable
     for those who are phlegmatic. In a word, in bodies which are warm
     either through nature, disease, time of life, season of the year,
     locality, or occupation, honey is productive of bile, whereas in
     opposite circumstances it produces blood.

     But surely it is impossible that the same article of diet can
     produce in certain persons bile and in others blood, if it be not
     that the genesis of these humours is accomplished in the body. For
     if all articles of food contained bile from the beginning and of
     themselves, and did not produce it by undergoing change in the
     animal body, then they would produce it similarly in all bodies;
     the food which was bitter to the taste would, I take it, be
     productive of bile, while that which tasted good and sweet would
     not generate even the smallest quantity of bile. Moreover, not
     only honey but all other sweet substances are readily converted
     into bile in the aforesaid bodies which are warm for any of the
     reasons mentioned.

     Well, I have somehow or other been led into this discussion,- not
     in accordance with my plan, but compelled by the course of the
     argument. This subject has been treated at great length by
     Aristotle and Praxagoras, who have correctly expounded the view of
     Hippocrates and Plato.

     9. For this reason the things that we have said are not to be
     looked upon as proofs but rather as indications of the dulness of
     those who think differently, and who do not even recognise what is
     agreed on by everyone and is a matter of daily observation. As for
     the scientific proofs of all this, they are to be drawn from these
     principles of which I have already spoken- namely, that bodies act
     upon and are acted upon by each other in virtue of the Warm, Cold,
     Moist and Dry. And if one is speaking of any activity, whether it
     be exercised by vein, liver, arteries, heart, alimentary canal, or
     any part, one will be inevitably compelled to acknowledge that
     this activity depends upon the way in which the four qualities are
     blended. Thus I should like to ask the Erasistrateans why it is
     that the stomach contracts upon the food, and why the veins
     generate blood. There is no use in recognizing the mere fact of
     contraction, without also knowing the cause; if we know this, we
     shall also be able to rectify the failures of function. "This is
     no concern of ours," they say; "we do not occupy ourselves with
     such causes as these; they are outside the sphere of the
     practitioner, and belong to that of the scientific investigator."
     Are you, then, going to oppose those who maintain that the cause
     of the function of every organ is a natural eucrasia, that the
     dyscrasia is itself known as a disease, and that it is certainly
     by this that the activity becomes impaired? Or, on the other hand,
     will you be convinced by the proofs which the ancient writers
     furnished? Or will you take a midway course between these two,
     neither perforce accepting these arguments as true nor
     contradicting them as false, but suddenly becoming sceptics-
     Pyrrhonists, in fact? But if you do this you will have to shelter
     yourselves behind the Empiricist teaching. For how are you going
     to be successful in treatment, if you do not understand the real
     essence of each disease? Why, then, did you not call yourselves
     Empiricists from the beginning? Why do you confuse us by
     announcing that you are investigating natural activities with a
     view to treatment? If the stomach is, in a particular case, unable
     to exercise its peristaltic and grinding functions, how are we
     going to bring it back to the normal if we do not know the cause
     of its disability? What I say is that we must cool the over-heated
     stomach and warm the warm the chilled one; so also we must moisten
     the one which has become dried up, and conversely; so, too, in
     combinations of these conditions; if the stomach becomes at the
     same time warmer and drier than normally, the first principle of
     treatment is at once to chill and moisten it; and if it become
     colder and moister, it must be warmed and dried; so also in other
     cases. But how on earth are the followers of Erasistratus going to
     act, confessing as they do that they make no sort of investigation
     into the cause of disease? For the fruit of the enquiry into
     activities is that by knowing the causes of the dyscrasiae one may
     bring them back to the normal, since it is of no use for the
     purposes of treatment merely to know what the activity of each
     organ is.

     Now, it seems to me that Erasistratus is unaware of this fact
     also, that the actual disease is that condition of the body which,
     not accidentally, but primarily and of itself, impairs the normal
     function. How, then, is he going to diagnose or cure diseases if
     he is entirely ignorant of what they are, and of what kind and
     number? As regards the stomach, certainly, Erasistratus held that
     one should at least investigate how it digests the food. But why
     was not investigation also made as to the primary originative
     cause of this? And, as regards the veins and the blood, he omitted
     even to ask the question "how?"

     Yet neither Hippocrates nor any of the other physicians or
     philosophers whom I mentioned a short while ago thought it right
     to omit this; they say that when the heat which exists naturally
     in every animal is well blended and moderately moist it generates
     blood; for this reason they also say that the blood is a virtually
     warm and moist humour, and similarly also that yellow bile is warm
     and dry, even though for the most part it appears moist. (For in
     them the apparently dry would seem to differ from the virtually
     dry.) Who does not know that brine and sea-water preserve meat and
     keep it uncorrupted, whilst all other water- the drinkable kind-
     readily spoils and rots it? And who does not know that when yellow
     bile is contained in large quantity in the stomach, we are
     troubled with an unquenchable thirst, and that when we vomit this
     up, we at once become much freer from thirst than if we had drunk
     very large quantities of fluid? Therefore this humour has been
     very properly termed warm, and also virtually dry. And, similarly,
     phlegm has been called cold and moist; for about this also clear
     proofs have been given by Hippocrates and the other Ancients.

     Prodicus also, when in his book "On the Nature of Man" he gives
     the name "phlegm" to that element in the humours which has been
     burned or, as it were, over-roasted, while using a different
     terminology, still keeps to the fact just as the others do; this
     man's innovations in nomenclature have also been amply done
     justice to by Plato. Thus, the white-coloured substance which
     everyone else calls phlegm, and which Prodicus calls blenna
     [mucus], is the well-known cold, moist humour which collects
     mostly in old people and in those who have been chilled in some
     way, and not even a lunatic could say that this was anything else
     than cold and moist.

     If, then, there is a warm and moist humour, and another which is
     warm and dry, and yet another which is moist and cold, is there
     none which is virtually cold and dry? Is the fourth combination of
     temperaments, which exists in all other things, non-existent in
     the humours alone? No; the black bile is such a humour. This,
     according to intelligent physicians and philosophers, tends to be
     in excess, as regards seasons, mainly in the fall of the year,
     and, as regards ages, mainly after the prime of life. And,
     similarly, also they say that there are cold and dry modes of
     life, regions, constitutions, and diseases. Nature, they suppose,
     is not defective in this single combination; like the three other
     combinations, it extends everywhere.

     At this point, also, I would gladly have been able to ask
     Erasistratus whether his "artistic" Nature has not constructed any
     organ for clearing away a humour such as this. For whilst there
     are two organs for the excretion of urine, and another of
     considerable size for that of yellow bile, does the humour which
     is more pernicious than these wander about persistently in the
     veins mingled with the blood? Yet Hippocrates says, "Dysentery is
     a fatal condition if it proceeds from black bile"; while that
     proceeding from yellow bile is by no means deadly, and most people
     recover from it; this proves how much more pernicious and acrid in
     its potentialities is black than yellow bile. Has Erasistratus,
     then, not read the book, "On the Nature of Man," any more than any
     of the rest of Hippocrates' writings, that he so carelessly passes
     over the consideration of the humours? Or, does the know it, and
     yet voluntarily neglect one of the finest studies in medicine?
     Thus he ought not to have said anything about the spleen, nor have
     stultified himself by holding that an artistic Nature would have
     prepared so large an organ for no purpose. As a matter of fact,
     not a matter of fact, not only Hippocrates and Plato- who are no
     less authorities on Nature than is Erasistratus- say that this
     viscus also is one of those which cleanse the blood, but there are
     thousands of the ancient physicians and philosophers as well who
     are in agreement with them. Now, all of these the high and mighty
     Erasistratus affected to despise, and he neither contradicted them
     nor even so much as mentioned their opinion. Hippocrates, indeed,
     says that the spleen wastes in those people in whom the body is in
     good condition, and all those physicians also who base themselves
     on experience agree with this. Again, in those cases in which the
     spleen is large and is increasing from internal suppuration, it
     destroys the body and fills it with evil humours; this again is
     agreed on, not only by Hippocrates, but also by Plato and many
     others, including the Empiric physicians. And the jaundice which
     occurs when the spleen is out of order is darker in colour, and
     the cicatrices of ulcers are dark. For, generally speaking, when
     the spleen is drawing the atrabiliary humour into itself to a less
     degree than is proper, the blood is unpurified, and the whole body
     takes on a bad colour. And when does it draw this in to a less
     degree than proper? Obviously, when it [the spleen] is in a bad
     condition. Thus, just as the kidneys, whose function it is to
     attract the urine, do this badly when they are out or order, so
     also the spleen, which has in itself a native power of attracting
     an atrabiliary quality,if it ever happens to be weak, must
     necessarily exercise this attraction badly, with the result that
     the blood becomes thicker and darker.

     Now all these points, affording as they do the greatest help in
     the diagnosis and in the cure of disease were entirely passed over
     by Erasistratus, and he pretended to despise these great men- he
     who does not despise ordinary people, but always jealously attacks
     the most absurd doctrines. Hence, it was clearly because he had
     nothing to say against the statements made by the Ancients
     regarding the function and utility of the spleen, and also because
     he could discover nothing new himself, that he ended by saying
     nothing at all. I, however, for my part, have demonstrated,
     firstly from the causes by which everything throughout nature is
     governed (by the causes I mean the Warm, Cold, Dry and Moist) and
     secondly, from obvious bodily phenomena, that there must needs be
     a cold and dry humour. And having in the next place drawn
     attention to the fact that this humour is black bile [atrabiliary]
     and that the viscus which clears it away is the spleen- having
     pointed this out by help of as few as possible of the proofs given
     by ancient writers, I shall now proceed to what remains of the
     subject in hand.

     What else, then, remains but to explain clearly what it is that
     happens in the generation of the humours, according to the belief
     and demonstration of the Ancients? This will be more clearly
     understood from a comparison. Imagine, then, some new wine which
     has been not long ago pressed from the grape, and which is
     fermenting and undergoing alteration through the agency of its
     contained heat. Imagine next two residual substances produced
     during this process of alteration, the one tending to be light and
     air-like and the other to be heavy and more of the nature of
     earth; of these the one, as I understand, they call the flower and
     the other the lees. Now you may correctly compare yellow bile to
     the first of these, and black bile to the latter, although these
     humours have not the same appearance when the animal is in normal
     health as that which they often show when it is not so; for then
     the yellow bile becomes vitelline, being so termed because it
     becomes like the yolk of an egg, both in colour and density; and
     again, even the black bile itself becomes much more malignant than
     when in its normal condition, but no particular name has been
     given to [such a condition of] the humour, except that some people
     have called it corrosive or acetose, because it also becomes sharp
     like vinegar and corrodes the animal's body- as also the earth, if
     it be poured out upon it- and it produces a kind of fermentation
     and seething, accompanied by bubbles- an abnormal putrefaction
     having become added to the natural condition of the black humour.
     It seems to me also that most of the ancient physicians give the
     name black humour and not black bile to the normal portion of this
     humour, which is discharged from the bowel and which also
     frequently rises to the top [of the stomach-contents]; and they
     call black bile that part which, through a kind of combustion and
     putrefaction, has had its quality changed to acid. There is no
     need, however, to dispute about names, but we must realise the
     facts, which are as follow:-

     In the genesis of blood, everything in the nutriment which belongs
     naturally to the thick and earth-like part of the food, and which
     does not take on well the alteration produced by the innate heat-
     all this the spleen draws into itself. On the other hand, that
     part of the nutriment which is roasted, so to speak, or burnt
     (this will be the warmest and sweetest part of it, like honey and
     fat), becomes yellow bile, and is cleared away through the
     so-called biliary vessels; now, this is thin, moist, and fluid,
     not like what it is when, having been roasted to an excessive
     degree, it becomes yellow, fiery, and thick, like the yolk of
     eggs; for this latter is already abnormal, while the previously
     mentioned state is natural. Similarly with the black humour: that
     which does not yet produce, as I say, this seething and
     fermentation on the ground, is natural, while that which has taken
     over this character and faculty is unnatural; it has assumed an
     acridity owing to the combustion caused by abnormal heat, and has
     practically become transformed into ashes. In somewhat the same
     way burned lees differ from unburned. The former is a warm
     substance, able to burn, dissolve, and destroy the flesh. The
     other kind, which has not yet undergone combustion, one may find
     the physicians employing for the same purposes that one uses the
     so-called potter's earth and other substances which have naturally
     a combined drying and chilling action.

     Now the vitelline bile also may take on the appearance of this
     combusted black bile, if ever it chance to be roasted, so to say,
     by fiery heat. And all the other forms of bile are produced, some
     the from blending of those mentioned, others being, as it were,
     transition-stages in the genesis of these or in their conversion
     into one another. And they differ in that those first mentioned
     are unmixed and unique, while the latter forms are diluted with
     various kinds of serum. And all the serums in the humours are
     waste substances, and the animal body needs to be purified from
     them. There is, however, a natural use for the humours first
     mentioned, both thick and thin; the blood is purified both by the
     spleen and by the bladder beside the liver, and a part of each of
     the two humours is put away, of such quantity and quality that, if
     it were carried all over the body, it would do a certain amount of
     harm. For that which is decidedly thick and earthy in nature, and
     has entirely escaped alteration in the liver, is drawn by the
     spleen into itself; the other part which is only moderately thick,
     after being elaborated [in the liver], is carried all over the
     body. For the blood in many parts of the body has need of a
     certain amount of thickening, as also, I take it, of the fibres
     which it contains. And the use of these has been discussed by
     Plato, and it will also be discussed by me in such of my treatises
     as may deal with the use of parts. And the blood also needs, not
     least, the yellow humour, which has as yet not reached the extreme
     stage of combustion; in the treatises mentioned it will be pointed
     out what purpose is subserved by this.

     Now Nature has made no organ for clearing away phlegm, this being
     cold and moist, and, as it were, half-digested nutriment; such a
     substance, therefore, does not need to be evacuated, but remains
     in the body and undergoes alteration there. And perhaps one cannot
     properly give the name of phlegm to the surplus-substance which
     runs down from the brain, but one should call it mucus [blenna] or
     coryza- as, in fact, it is actually termed; in any case it will be
     pointed out, in the treatise "On the Use of Parts," how Nature has
     provided for the evacuation of this substance. Further, the device
     provided by Nature which ensures that the phlegm which forms in
     the stomach and intestines may be evacuated in the most rapid and
     effective way possible- this also will be described in that
     commentary. As to that portion of the phlegm which is carried in
     the veins, seeing that this is of service to the animal, it
     requires no evacuation. Here too, then, we must pay attention and
     recognise that, just as in the case of each of the two kinds of
     bile, there is one part which is useful to the animal and in
     accordance with its nature, while the other part is useless and
     contrary to nature, so also is it with the phlegm; such of it as
     is sweet is useful to the animal and according to nature, while,
     as to such of it as has become bitter or salt, that part which is
     bitter is completely undigested, while that part which is salt has
     undergone putrefaction. And the term "complete indigestion" refers
     of course to the second digestion- that which takes place in the
     veins; it is not a failure of the first digestion- that in the
     alimentary canal- for it would not have become a humour at the
     outset if it had escaped this digestion also.

     It seems to me that I have made enough reference to what has been
     said regarding the genesis and destruction of humours by
     Hippocrates, Plato, Aristotle, Praxagoras, and Diocles, and many
     others among the Ancients; I did not deem it right to transport
     the whole of their final pronouncements into this treatise. I have
     said only so much regarding each of the humours as will stir up
     the reader, unless he be absolutely inept, to make himself
     familiar with the writings of the Ancients, and will help him to
     gain more easy access to them. In another treatise I have written
     on the humours according to Praxagoras, to Praxagoras, son of
     authority Nicarchus; although this authority makes as many as ten
     humours, not including the blood (the blood itself being an
     eleventh), this is not a departure from the teaching of
     Hippocrates; for Praxagoras divides into species and varieties the
     humours which Hippocrates first mentioned, with the demonstration
     proper to each.

     Those, then, are to be praised who explain the points which have
     been duly mentioned, as also those who add what has been left out;
     for it is not possible for the same man to make both a beginning
     and an end. Those, on the other hand, deserve censure who are so
     impatient that they will not wait to learn any of the things which
     have been duly mentioned, as do also those who are so ambitious
     that, in their lust after novel doctrines, they are always
     attempting some fraudulent sophistry, either purposely neglecting
     certain subjects, as Erasistratus does in the case of the humours,
     or unscrupulously attacking other people, as does this same
     writer, as well as many of the more recent authorities.

     But let this discussion come to an end here, and I shall add in
     the third book all that remains.